ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R09-OAR-2011-0638; FRL-_________________]

Approval and Promulgation of Air Quality Implementation Plans; 

California; Determinations of Failure to Attain the One-Hour 

Ozone Standard

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

SUMMARY: The EPA is proposing to determine that three areas in 

California, previously designated nonattainment for the one-hour 

ozone national ambient air quality standard (NAAQS), did not 

attain that standard by their applicable attainment dates: the 

Los Angeles-South Coast Air Basin Area (―South Coast‖), the San 

Joaquin Valley Area (―San Joaquin Valley‖), and the Southeast 

Desert Modified Air Quality Maintenance Area (―Southeast 

Desert‖). These proposed determinations are based on three years 

of quality-assured and certified ambient air quality monitoring 

data for the period preceding the applicable attainment 

deadline.

DATES: Written comments must be received on or before [Insert 

date 30 days from date of publication in the Federal Register].

ADDRESSES: Submit your comments, identified by Docket No. EPAR09-OAR-2011-0638, by one of the following methods:
2

1. Federal Rulemaking Portal: http://www.regulations.gov. 

Follow the on-line instructions for submitting comments.

2. E-mail: Doris Lo at lo.doris@epa.gov.

3. Fax: Doris Lo, Air Planning Office (AIR-2), at fax number 

415-947-3579.

4. Mail: Doris Lo, Air Planning Office (AIR-2), U.S. 

Environmental Protection Agency, Region IX, 75 Hawthorne, 

San Francisco, California 94105.

5. Hand or Courier Delivery: Doris Lo, Air Planning Section 

(AIR-2), U.S. Environmental Protection Agency, Region IX, 

75 Hawthorne, San Francisco, California 94105. Such 

deliveries are only accepted during the Docket's normal 

hours of operation. Special arrangements should be made for 

deliveries of boxed information.

Instructions: Direct your comments to Docket ID No. EPA-R09-

OAR-2011-0638. EPA's policy is that all comments received will 

be included in the public docket without change and may be made 

available online at www.regulations.gov, including any personal 

information provided, unless the comment includes information 

claimed to be Confidential Business Information (CBI) or other 

information the disclosure of which is restricted by statute. 

Do not submit information through www.regulations.gov or e-mail 

that you consider to be CBI or otherwise protected from 

disclosure. The www.regulations.gov website is an anonymous 
3

access system, which means EPA will not know your identity or 

contact information unless you provide it in the body of your 

comment. If you send an e-mail comment directly to EPA without 

going through www.regulations.gov, your e-mail address will be 

automatically captured and included as part of the comment that 

is placed in the public docket and made available on the 

Internet. If you submit an electronic comment, EPA recommends 

that you include your name and other contact information in the 

body of your comment and with any disk or CD-ROM you submit. If 

EPA cannot read your comment due to technical difficulties and 

cannot contact you for clarification, EPA may not be able to 

consider your comment. Electronic files should avoid the use of 

special characters, any form of encryption, and be free of any 

defects or viruses.

Docket: All documents in the docket are listed in the 

www.regulations.gov index. Although listed in the index, some 

information is not publicly available, e.g., CBI or other 

information whose disclosure is restricted by statute. Certain 

other material, such as copyrighted material, will be publicly 

available only in hard copy. Publicly available docket materials 

are available either electronically in www.regulations.gov or in 

hard copy at the Air Planning Office (Air-2), U.S. Environmental 

Protection Agency, Region IX, 75 Hawthorne Street, San 

Francisco, California 94105. EPA requests that if at all 
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possible, you contact the person listed in the FOR FURTHER 

INFORMATION CONTACT section to schedule your inspection during 

normal business hours.

FOR FURTHER INFORMATION CONTACT: Doris Lo, (415) 972-3959, or 

by email at lo.doris@epa.gov. 

SUPPLEMENTARY INFORMATION: Throughout this document whenever 

―we,‖ ―us,‖ or ―our‖ is used, we mean EPA.

Table of Contents

I. What Actions Is EPA Taking?

II. Background

III. What Is EPA's Analysis?

A. South Coast One-Hour Ozone Nonattainment Area

B. San Joaquin Valley One-Hour Ozone Nonattainment Area

C. Southeast Desert One-Hour Ozone Nonattainment Area

IV. What Is The Effect Of The Proposed Determinations?

V. Proposed Actions

VI. Statutory and Executive Order Reviews

I. What Actions Is EPA Taking?

EPA is proposing to determine, under the Clean Air Act (CAA 

or ―Act‖), that three areas previously designated nonattainment 

for the one-hour ozone NAAQS -- the South Coast, the San Joaquin 

Valley, and the Southeast Desert -- failed to attain the NAAQS 

for one-hour ozone by their applicable one-hour NAAQS attainment 

dates.
5

II. Background

Regulatory Context

The Act requires us to establish NAAQS for certain 

widespread pollutants that cause or contribute to air pollution 

that is reasonably anticipated to endanger public health or 

welfare (sections 108 and 109 of the Act). In 1979, we 

promulgated the revised one-hour ozone standard of 0.12 parts 

per million (ppm) (44 FR 8202, February 8, 1979).1

An area is considered to have attained the one-hour ozone 

standard if there are no violations of the standard, as 

determined in accordance with the regulation codified at 40 CFR 

section 50.9, based on three consecutive calendar years of 

complete, quality-assured and certified monitoring data. A 

violation occurs when the ambient ozone air quality monitoring 

data show greater than one (1.0) ―expected number‖ of 

exceedances per year at any site in the area, when averaged over 

three consecutive calendar years.2 An exceedance occurs when the 

maximum hourly ozone concentration during any day exceeds 0.124 

ppm. For more information, please see ―National 1-hour primary 

 

1 For ease of communication, many reports of ozone concentrations are given 

in parts per billion (ppb); ppb = ppm × 1000. Thus, 0.12 ppm becomes 120 ppb 

(or between 120 to 124 ppb, when rounding is considered).

2 An ―expected number‖ of exceedances is a statistical term that refers to an 

arithmetic average. An ―expected number‖ of exceedances may be equivalent to 

the number of observed exceedances plus an increment that accounts for 

incomplete sampling. See, 40 CFR part 50, appendix H. Because, in this 

context, the term ―exceedances‖ refers to days (during which the daily 

maximum hourly ozone concentration exceeded 0.124 ppm), the maximum possible 

number of exceedances in a given year is 365 (or 366 in a leap year).
6

and secondary ambient air quality standards for ozone‖ (40 CFR 

50.9) and ―Interpretation of the 1-Hour Primary and Secondary 

National Ambient Air Quality Standards for Ozone‖ (40 CFR part 

50, appendix H).

The Act, as amended in 1990, required EPA to designate as 

nonattainment any area that was violating the one-hour ozone 

standard, generally based on air quality monitoring data from 

the 1987 through 1989 period (section 107(d)(4) of the Act; 56 

FR 56694, November 6, 1991). The Act further classified these 

areas, based on the severity of their nonattainment problem, as 

Marginal, Moderate, Serious, Severe, or Extreme. 

The control requirements and date by which attainment of 

the one-hour ozone standard was to be achieved varied with an 

area’s classification. Marginal areas were subject to the fewest 

mandated control requirements and had the earliest attainment 

date, November 15, 1993, while Severe and Extreme areas were 

subject to more stringent planning requirements and were 

provided more time to attain the standard. Two measures that are 

triggered if a Severe or Extreme area fails to attain the 

standard by the applicable attainment date are contingency 

measures [section 172(c)(9)] and a major stationary source fee

provision [sections 182(d)(3) and 185)](―major source fee

program‖ or ―section 185 fee program‖).

Designations and Classifications 
7

On November 6, 1991, EPA designated the South Coast3 as 

―Extreme‖ nonattainment for the one-hour ozone standard, with an 

attainment date no later than November 15, 2010 (56 FR 56694). 

In its November 6, 1991 final rule, EPA designated the San 

Joaquin Valley4 as ―Serious‖ nonattainment for the one-hour ozone 

standard, but later reclassified the valley as ―Severe‖ (66 FR 

56476, November 8, 2001), and then as ―Extreme‖ (69 FR 20550, 

April 16, 2004) for the one-hour ozone standard, with the same 

attainment date (November 15, 2010) as the South Coast. In its 

1991 final rule, EPA designated the Southeast Desert5 as ―Severe17‖ nonattainment for the one-hour ozone standard, with an 

attainment date no later than November 15, 2007. 

Outside of Indian country6, the South Coast lies within the 

jurisdiction of the South Coast Air Quality Management District 

(SCAQMD). Similarly, with the exception of Indian country, San 

Joaquin Valley lies within the San Joaquin Valley Unified Air 

 

3 The South Coast includes Orange County, the southwestern two-thirds of Los 

Angeles County, southwestern San Bernardino County, and western Riverside 

County (see 40 CFR section 81.305).

4 San Joaquin Valley includes all of Fresno, Kings, Madera, Merced, San 

Joaquin, Stanislaus, and Tulare counties, as well as the western half of Kern 

County (see 40 CFR section 81.305).

5 The Southeast Desert covers the Victor Valley/Barstow region in San 

Bernardino County, the Coachella Valley region in Riverside County, and the 

Antelope Valley portion of Los Angeles County (see 40 CFR section 81.305). 

6 ―Indian country‖ as defined at 18 U.S.C. 1151 refers to: ―(a) all land 

within the limits of any Indian reservation under the jurisdiction of the 

United States Government, notwithstanding the issuance of any patent, and, 

including rights-of-way running through the reservation, (b) all dependent 

Indian communities within the borders of the United States whether within the 

original or subsequently acquired territory thereof, and whether within or 

without the limits of a state, and (c) all Indian allotments, the Indian 

titles to which have not been extinguished, including rights-of-way running

through the same.‖
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Pollution Control District (SJVUAPCD). Likewise, excluding 

Indian country, the Los Angeles portion of the Southeast Desert 

lies within the Antelope Valley Air Quality Management District 

(AVAQMD), the San Bernardino County portion of the Southeast 

Desert lies within the Mojave Desert Air Quality Management 

District (MDAQMD), and the Riverside County portion of the 

Southeast Desert lies within the SCAQMD.

Under California law, each air district is responsible for 

adopting and implementing stationary source rules, such as the 

fee program rules required under CAA section 185, while the 

California Air Resources Board (CARB) adopts and implements 

consumer products and mobile source rules. The district and 

state rules are submitted to EPA by CARB.

Transition from One-Hour Ozone Standard to Eight-Hour Ozone 

Standard

In 1997, EPA promulgated a new, more protective standard 

for ozone based on an eight-hour average concentration (the 1997 

eight-hour ozone standard). In 2004, EPA published the 1997 

eight-hour ozone designations and classifications and a rule 

governing certain facets of implementation of the eight-hour 

ozone standard (Phase 1 Rule) (69 FR 23858 and 69 FR 23951, 

respectively, April 30, 2004).

Although EPA revoked the one-hour ozone standard (effective 

June 15, 2005), to comply with anti-backsliding requirements of 
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the Act, eight-hour ozone nonattainment areas remain subject to 

certain requirements based on their one-hour ozone 

classification. Initially, in our rules to address the 

transition from the one-hour to the eight-hour ozone standard,

EPA did not include contingency measures or the section 185 fee 

program among the measures retained as one-hour ozone antibacksliding requirements.

7 However, on December 23, 2006, the 

United States Court of Appeals for the District of Columbia 

Circuit determined that EPA should not have excluded these

requirements from its anti-backsliding requirements. South Coast 

Air Quality Management District v. EPA, 472 F.3d 882 (D.C. Cir. 

2006) reh’g denied 489 F.3d 1245 (clarifying that the vacatur 

was limited to the issues on which the court granted the 

petitions for review).

Thus, the Court vacated the provisions that excluded these 

requirements. As a result, States must continue to meet the 

obligations for one-hour ozone NAAQS contingency measures and, 

for Severe and Extreme areas, major source fee programs. EPA has 

issued a proposed rule that would remove the vacated provisions 

of 40 CFR 51.905(e), and that addresses contingency measures for 

failure to attain or make reasonable further progress toward 

attainment of the one-hour standard. See 74 FR 2936, January 16, 

 

7 Final Rule to Implement the 8-Hour Ozone National Ambient Air Quality 

Standard—Phase 1, 69 FR 23951 (April 30, 2004).
10

2009 (proposed rule); 74 FR 7027, February 12, 2009 (notice of 

public hearing and extension of comment period).

Rationale for Today’s Proposed Action

After revocation of the one-hour ozone standard, EPA must 

continue to provide a mechanism to give effect to the one-hour 

anti-backsliding requirements. See SCAQMD v. EPA, 47 F.3d 882, 

at 903. In keeping with this responsibility with respect to onehour anti-backsliding contingency measures and section 185 fee 

programs for these three California areas, EPA proposes to 

determine that each area failed to attain the one-hour ozone 

standard by its applicable attainment date.

III. What Is EPA's Analysis?

A determination of whether an area’s air quality meets the 

one-hour ozone standard is generally based upon three years of 

complete8, quality-assured and certified air quality monitoring 

data gathered at established State and Local Air Monitoring 

Stations (―SLAMS‖) in the nonattainment area and entered into 

the EPA’s Air Quality System (AQS) database. Data from air 

monitors operated by state/local agencies in compliance with EPA 

monitoring requirements must be submitted to the AQS database. 

Monitoring agencies annually certify that these data are 

 

8 Generally, a ―complete‖ data set for determining attainment of the ozone is 

one that includes three years of data with an average percent of days with 

valid monitoring data greater than 90% with no single year less than 75%. See 

40 CFR part 50, appendix I. There are less stringent data requirements for 

showing that a monitor has failed an attainment test and thus has recorded a 

violation of the standard.
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accurate to the best of their knowledge. Accordingly, EPA relies 

primarily on data in its AQS database when determining the 

attainment status of an area. See 40 CFR section 50.9; 40 CFR 

part 50, appendix H; 40 CFR part 53; 40 CFR part 58, appendices 

A, C, D and E. All data are reviewed to determine the area’s air 

quality status in accordance with 40 CFR part 50, appendix H. 

Under EPA regulations at 40 CFR section 50.9, the one-hour 

ozone standard is attained at a monitoring site when the 

expected number of days per calendar year with maximum hourly 

average concentrations above 0.12 parts per million (235 

micrograms per cubic meter) is equal to or less than 1, as 

determined by 40 CFR part 50, appendix H.9

EPA proposes to determine that the South Coast, the San 

Joaquin Valley, and the Southeast Desert failed to attain the 

one-hour ozone standard by their applicable attainment dates; 

that is, the number of expected exceedances at sites in each of

the three nonattainment areas was greater than one per year in 

the period prior to the applicable attainment date. These

proposed determinations are based on three years of qualityassured and certified ambient air quality monitoring data in AQS 

for the 2008-2010 monitoring period for the South Coast and the 

 

9 The average number of expected exceedances is determined by averaging the 

expected exceedances of the one-hour ozone standard over a consecutive three 

calendar year period. See 40 CFR part 50 appendix H.
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San Joaquin Valley, and quality-assured and certified data in 

AQS for 2005-2007 for the Southeast Desert. 

A. South Coast One-Hour Ozone Nonattainment Area

In the South Coast, the South Coast Air Quality Management 

District (SCAQMD) is responsible for assuring that the area 

meets air quality monitoring requirements. SCAQMD Annual Network 

Plans describe the air monitoring network and discuss its

status, as required under 40 CFR section 58.10.

Since 2007, EPA has regularly reviewed these annual plans 

for compliance with the applicable reporting requirements in 40 

CFR part 58. With respect to ozone, EPA has found that the 

area’s network plans meet the applicable requirements under 40 

CFR part 58.10 Furthermore, we concluded in our Technical System 

Audit of the SCAQMD network conducted during April 2010, that 

the ambient air monitoring network operated by SCAQMD network 

currently meets or exceeds the requirements for the minimum 

number of SLAMS monitoring sites for all criteria pollutants, 

and that all of the required ozone monitoring sites are properly 

located with respect to monitoring objectives, spatial scales 

and other site criteria, as required by 40 CFR part 58, appendix 

 

10 See, e.g., letter from Matthew Lakin, Manager, Air Quality Analysis 

Office, Air Division, EPA Region IX, to Dr. Chung S. Liu, Deputy Executive 

Officer, Science and Technology Advancement, SCAQMD, dated November 1, 2010, 

approving SCAQMD’s 2009 Annual Air Quality Monitoring Network Plan. 
13

D.11 Also, SCAQMD annually certifies that the data it submits to 

AQS are quality-assured.12

There were 29 ozone monitoring sites located throughout the 

South Coast in calendar years 2008 through 2010: 13 within Los 

Angeles County, four within Orange County, seven within 

Riverside County, and five within San Bernardino County.13 All 

SCAQMD sites monitor ozone concentrations on a continuous basis 

using ultraviolet absorption monitors.14 SCAQMD administered 28 

of the 29 sites, and one was administered by the Morongo Band of 

Mission Indians. Table 1 summarizes the ozone monitoring data 

from the various monitoring sites in the South Coast Air Basin 

by showing the expected exceedances per year and as an average 

over the 2008-2010 period. The data summarized in Table 1 are

considered complete for the purposes of determining if the 

standard is met.

15

 

11 See letter from Deborah Jordan, Director, Air Division, U.S. EPA Region 

IX, to Barry Wallerstein, Executive Officer, SCAQMD, dated March 14, 2011, 

and enclosure titled, ―Technical System Audit Report, South Coast Air Quality 

Management District, April 13-April 16, 2010.‖

12 See, e.g., letter from Chung S. Liu, Deputy Executive Office, Science and 

Technology Advancement, SCAQMD, to Jared Blumenfeld, Regional Administrator, 

U.S. EPA Region IX, certifying 2009 ozone data.

13 See figure 1 in appendix A to SCAQMD’s Annual Air Quality Monitoring 

Network Plan (July 2010) for a map of SCAQMD’s ozone monitors in the South 

Coast.

14 SCAQMD operates federal equivalent method (FEM) monitors for ozone, 

specifically, Thermo Electron model 49i and Teledyne/API 400 series 

ultraviolet absorption monitors. See SCAQMD’s Annual Air Quality Monitoring 

Network Plan (July 2010). These monitoring devices have an EPA designation 

number EQOA-0880-047 and EQOA-0992-087, respectively. See EPA ―List of 

Designated Reference and Equivalent Methods, page 27 (February 1, 2011), 

available on the Internet at: http://www.epa.gov/ttn/amtic/criteria.html.

15 The criteria for data completeness are met at most of the ozone monitors 

over the 2008-2010 period, but are not met for the ozone monitors at certain 
14

Table 1 – One-Hour Ozone Data for the South Coast One-Hour Ozone 

Nonattainment Area

General Location Site (AQS ID)

Expected 

Exceedances by 

Year

Expected 

Exceedances 

3-yr average

2008 2009 2010 2008-2010

LOS ANGELES COUNTY:

East San Gabriel 

Valley

Azusa

(06-037-0002)

7.0 4.0 0.0 3.6

East San 

Fernando Valley

Burbank

(06-037-1002)

1.0 1.0 0.0 0.7

South Central 

Los Angeles 

Countya

Lynwood/Compton

(06-037-

1301/06-037-

1302)

0.0 0.0 0.0 0.0

East San Gabriel 

Valley

Glendora

(06-037-0016)

12.0 7.4 0.0 6.5

Southwest 

Coastal LA 

County

Los Angeles –

LAX

(06-037-5005)

0.0 0.0 0.0 0.0

South Coastal LA 

County

North Long 

Beach

(06-037-4002)

0.0 0.0 0.0 0.0

Central Los 

Angles

Los Angeles –

N. Main Street

(06-037-1103)

0.0 1.0 0.0 0.3

West San Gabriel 

Valley

Pasadena

(06-037-2005)

0.0 3.0 0.0 1.0

South San 

Gabriel Valley

Pico Rivera

(06-037-1602)

0.0 1.0 0.0 0.3

Pomona/Walnut 

Valley

Pomona

(06-037-1701)

5.0 1.0 0.0 2.0

West San 

Fernando Valley

Reseda

(06-037-1201)

0.0 1.0 0.0 0.3

Santa Clarita Santa Clarita 8.1 5.1 1.1 4.8

 

stations over the 2008-2010 period: Pomona, Morongo Reservation, Mira Loma 

(Jurupa High School), and Fontana. However, with respect to these four 

monitors, the failure to meet the completeness criteria does not bear on the 

question of whether the data is complete for the purposes of this 

determination because there are sufficient observed exceedances during the 

relevant three-year period to establish that the standard was not met by the 

applicable attainment date at those sites. See 40 CFR part 50, appendix H, 

section 3, first paragraph.
15

Valley (06-037-6012)

Northwest 

Coastal LA 

County

West Los 

Angeles

(06-037-0113) 

0.0 1.0 0.0 0.3

ORANGE COUNTY:

Central Orange 

County

Anaheim

(06-059-0007)

0.0 0.0 0.0 0.0

North Coastal 

Orange County

Costa Mesa

(06-059-1003)

0.0 0.0 0.0 0.0

North Orange 

County

La Habra

(06-059-5001)

0.0 0.0 0.0 0.0

Saddleback 

Valley

Mission Viejo

(06-059-2022)

0.0 0.0 0.0 0.0

RIVERSIDE COUNTY:

Banning Airport Banning

(06-065-0012)

10.0 1.0 0.0 3.7

Banning Airportb Morongo 

Reservation 

(06-065-1016)

12.1 2.7 4.0 6.3

Lake Elsinore Lake Elsinore

(06-065-9001)

6.1 1.0 0.0 2.4

Mira Loma Mira Loma –

Jurupa High 

School

(06-065-0004)

6.9 1.1 0.0 2.7

Mira Loma Mira Loma – Van 

Buren

(06-065-8005)

4.0 0.0 0.0 1.3

Perris Valley Perris

(06-065-6001)

4.0 1.0 0.0 1.7

Metropolitan 

Riverside County

Rubidoux

(06-065-8001)

8.0 0.0 1.0 3.0

SAN BERNARDINO COUNTY:

Central San 

Bernardino 

Mountains 

Crestline

(06-071-0005)

16.2 7.0 8.0 10.4

Central San 

Bernardino 

Valley

Fontana

(06-071-2002)

8.1 3.0 2.8 4.6

East San 

Bernardino 

Valley

Redlands

(06-071-4003)

12.0 1.0 1.0 4.7

Central San 

Bernardino 

Valley

San Bernardino

(06-071-9004)

11.1 2.0 1.0 4.7

Northwest San Upland 9.1 3.0 1.0 4.4
16

Bernardino 

Valley

(06-071-1004)

a Data for year 2008 is from the Lynwood monitor, which was 

relocated to Compton in late 2008.

b This site is run by the Morongo Tribe of Mission Indians on 

the Morongo Reservation. It is not part of the SCAQMD monitoring 

network.

Source: Quicklook Report, June 16, 2011 (in the docket to this 

proposed action).

Generally, the highest ozone concentrations in the South 

Coast occur in the northern and eastern portions of the area. As 

shown in Table 1, the highest three-year average of expected 

exceedances at any site in the South Coast Air Basin for 2008-

2010 is 10.4 (at Crestline, a site located at 4,500 feet 

elevation in the San Bernardino Mountains). The calculated 

exceedance rate of 10.4 represents a violation of the one-hour 

ozone standard (a three-year average of expected exceedances 

less than or equal to 1). For more information, please see 

―National 1-hour primary and secondary ambient air quality 

standards for ozone‖ (40 CFR section 50.9) and ―Interpretation 

of the 1-Hour Primary and Secondary National Ambient Air Quality 

Standards for Ozone‖ (40 CFR part 50, appendix H). Table 1 also 

shows that, while the most frequent violations occur in the San 

Bernardino Mountains, violations are widespread in eastern 

Riverside County and southwestern San Bernardino County as well 

as the Santa Clarita and east San Gabriel valleys in Los Angeles 

County.
17

Taking into account the extent and reliability of the 

applicable ozone monitoring network, and the data collected 

therefrom and summarized in Table 1, we propose to determine 

that the South Coast Air Basin failed to attain the one-hour 

ozone standard (as defined in 40 CFR part 50, appendix H) by the 

applicable attainment date (i.e., November 15, 2010).

B. San Joaquin Valley One-Hour Ozone Nonattainment Area

In the San Joaquin Valley, CARB and San Joaquin Valley 

Unified Air Pollution Control District (SJVUAPCD) are the 

agencies responsible for assuring that the area meets air 

quality monitoring requirements. The SLAMS network of ozone 

monitors in the valley includes monitors operated by SJVUAPCD 

and monitors operated by CARB. SJVUAPCD submits annual 

monitoring network plans to EPA. SJVUAPCD Network Plans describe 

the various monitoring sites operated by SJVUAPCD as well as 

those operated by CARB. These plans discuss the status of the 

air monitoring network, as required under 40 CFR section 58.10.

See SJVUAPCD’s Air Monitoring Network Plan, dated June 30, 2010.

As noted above for the South Coast, EPA regularly reviews 

these annual plans for compliance with the applicable reporting 

requirements in 40 CFR part 58. With respect to ozone, EPA has 

found that the area’s network plans meet the applicable 
18

requirements under 40 CFR part 58.16 Furthermore, we concluded in 

our Technical System Audit of the CARB Primary Quality Assurance 

Organization (PQAO),17 conducted during summer 2007, that, with 

one exception, the combined ambient air monitoring network 

operated by CARB and SJVUAPCD in the San Joaquin Valley

currently meets or exceeds the requirements for the minimum 

number of SLAMS monitoring sites for ozone. In our audit, we 

found that our regulations required an additional ozone monitor 

in the Visalia-Porterville Metropolitan Statistical Area (MSA) 

to meet the minimum SLAMS monitoring requirements. In response, 

SJVUAPCD opened an ozone monitoring station in Porterville. The 

new station began reporting ozone data in March 2010. CARB 

annually certifies that the data the agency submits to AQS are 

quality-assured, including data collected by CARB at monitoring 

sites in San Joaquin Valley.

18 SJVUAPCD does the same for 

monitors operated by the District.19

 

16 See, e.g., letter from Matthew Lakin, Manager, Air Quality Analysis 

Office, Air Division, EPA Region IX, to Scott Nester, Planning Director, 

SJVUAPCD, dated November 1, 2010, approving SJVUAPCD’s 2009 Ambient Air 

Monitoring Network Plan.

17 A primary quality assurance organization is responsible for a group of

monitoring stations for which data quality assessments can be pooled. See 40 

CFR section 58.1. CARB is the lead PQAO for all the air districts in the 

Sacramento Metro Area.

18 See, e.g., letter from Karen Magliano, Chief, Air Quality Data Branch, 

Planning and Technical Support Division, CARB, to Jared Blumenfeld, Regional 

Administrator, U.S. EPA Region IX, certifying calendar year 2010 ambient air 

quality data and quality assurance data, dated April 28, 2011.

19 See, e.g., letter from Seyed Sadredin, Executive Director/Air Pollution 

Control Officer, letter to Jared Blumenfeld, Regional Administrator, U.S. EPA 

Region IX, certifying in part calendar year 2010 ambient air quality data and 

quality assurance data, dated June 13, 2011. The District’s 2010 partial 

certification dated June 13, 2011 covered ozone data. 
19

There were 22 ozone monitoring sites located throughout the 

San Joaquin Valley in calendar years 2008 through 2010: six

within Kern County, five within Fresno County, three within 

Tulare County, two within Kings, San Joaquin and Stanislaus 

counties, and one each in Madera and Merced counties.

20 All of 

the sites monitor ozone concentrations on a continuous basis 

using ultraviolet absorption monitors. CARB or SJVUAPCD operate 

19 of the 22 ozone monitoring sites; the National Park Service 

operates two ozone monitoring sites in Sequoia National Park in 

Tulare County; and the Tachi-Yokut Tribe operates an ozone 

monitor at the Santa Rosa Rancheria in Kings County.

Table 2 summarizes the ozone monitoring data from the 

various monitoring sites in the San Joaquin Valley by showing 

the expected exceedances per year and as an average over the 

2008-2010 period. The data summarized in Table 2 are considered 

complete for the purposes of determining if the standard is 

met.

21

 

20 See figure 1 in SJVUAPCD’s Air Monitoring Network Plan (June 30, 2010) for 

a map of the ozone monitors in the San Joaquin Valley. 

21 The criteria for data completeness are met at most of the ozone monitors 

over the 2008-2010 period, but are not met for the ozone monitors at certain 

stations over the 2008-2010 period: Fresno (Drummond Street), Clovis, 

Hanford/Corcoran, and Sequoia National Park (06-017-0009). However, with 

respect to all of these monitors except for Fresno (Drummond Street), the 

failure to meet the completeness criteria does not bear on the question of 

whether the data is complete for the purposes of this determination because 

there are sufficient observed exceedances during the relevant three-year 

period to establish that the standard was not met by the applicable 

attainment date at those sites. See 40 CFR part 50, appendix H, section 3, 

first paragraph. Moreover, despite the lack of complete data from Fresno 

(Drummond Street), sufficient data from the network as a whole exist to 
20

Table 2 – One-Hour Ozone Data for the San Joaquin Valley OneHour Ozone Nonattainment Area

Site (AQS ID)

Expected 

Exceedances by 

Year

Expected 

Exceedances 

3-yr average

2008 2009 2010 2008-2010

FRESNO COUNTY:

Clovis

(06-019-5001)

8.3 0.0 3.0 3.8

Fresno – Drummond Street

(06-019-0007)

0.0 0.0 0.0 0.0

Fresno – North First Street 

(06-019-0008)

7.1 0.0 2.0 3.0

Fresno – Sierra Skypark #2

(06-019-0242)

2.1 0.0 2.4 1.5

Parlier

(06-019-4001)

2.0 0.0 1.1 1.0

KERN COUNTY:

Arvin

(06-029-5001)

14.3 3.1 2.4 6.6

Bakersfield

(06-029-0014)

1.0 0.0 0.0 0.3

Edison

(06-029-0007)

5.0 2.0 1.0 2.7

Maricopa

(06-029-0008)

0.0 0.0 0.0 0.0

Oildale

(06-029-0232)

0.0 0.0 0.0 0.0

Shafter

(06-029-6001)

1.0 0.0 0.0 0.3

KINGS COUNTY:

Hanford/Corcorana

(06-031-1004/06-031-0004)

4.4 0.0 2.7 2.4

Santa Rosa Rancheria

(06-031-0500)

2.2 0.0 0.0 0.7

MADERA COUNTY:

Madera

(06-039-0004)

0.0 0.0 0.0 0.0

MERCED COUNTY:

Merced

(06-047-0003)

3.1 0.0 0.0 1.0

SAN JOAQUIN COUNTY:

 

support the proposed determination of failure to attain the one-hour ozone 

NAAQS by the applicable attainment date within the San Joaquin Valley.
21

Stockton

(06-077-1002)

0.0 0.0 0.0 0.0

Tracy

(06-077-3005)

0.0 0.0 0.0 0.0

STANISLAUS COUNTY:

Modesto

(06-099-0005)

1.0 0.0 0.0 0.3

Turlock

(06-099-0006)

3.0 1.0 0.0 1.3

TULARE COUNTY:

Sequoia National Park – Lower 

Kaweah 

(06-107-0006)

1.0 0.0 0.0 0.3

Sequoia National Park – Sequoia 

and Kings Canyon Nat’l Park

(06-107-0009)

6.9 0.0 0.0 2.3

Visalia

(06-107-2002)

3.0 0.0 0.0 1.0

a The data reflect the combined data from the Corcoran site 

(2008 and 2009) and the Hanford site (2010). The Hanford site 

was closed due to renovation during 2008 and 2009, and an ozone 

monitor was added to the Corcoran site to serve as a temporary 

replacement during the renovation.

Source: Quicklook Report, May 19, 2011 (in the docket to this 

proposed action).

It should be noted that CARB and SJVUAPCD have flagged 

certain ozone exceedances in years 2008 and 2010 as exceptional 

events,22 but because EPA has not yet concurred on, or determined 

to exclude, any of the flagged events, Table 2 includes the

flagged data. Generally, the highest ozone concentrations in San 

 

22 Under CAA section 319(b)(1)(A), the term ―exceptional event‖ means an 

event that--(i) affects air quality; (ii) is not reasonably controllable or 

preventable; (iii) is an event caused by human activity that is unlikely to 

recur at a particular location or a natural event; and (iv) is determined by 

the Administrator through the process established in the regulations 

promulgated under paragraph (2) to be an exceptional event. Under CAA section 

319(b)(1)(B), the term ―exceptional event‖ does not include--(i) stagnation 

of air masses or meteorological inversions; (ii) a meteorological event 

involving high temperatures or lack of precipitation; or (iii) air pollution 

relating to source noncompliance. EPA’s regulations referred to in CAA 

section 309(b)(1)(A) were promulgated at 40 CFR 50.14.
22

Joaquin Valley occur in the central (i.e., in and around the 

city of Fresno) and the southern portions (i.e., southeast of 

Bakersfield) of the area. As shown in Table 2, the highest 

three-year average of expected exceedances at any site in the 

San Joaquin Valley for 2008-2010 is 6.6 at Arvin, a site located 

with mountains to the east, west, and south. The calculated 

exceedance rate of 6.6 represents a violation of the one-hour 

ozone standard (a three-year average of expected exceedances 

less than or equal to 1). Even if EPA were to concur on all of 

the flagged exceedances and determine that they qualify for 

exclusion for the purpose of determining attainment, the 

calculated exceedance rate at Arvin would be 3.9, which still 

constitutes a violation of the standard.

Taking into account the extent and reliability of the 

applicable ozone monitoring network, and the data collected 

therefrom and summarized in Table 2, we propose to determine 

that the San Joaquin Valley failed to attain the one-hour ozone 

standard (as defined in 40 CFR part 50, appendix H) by the 

applicable attainment date (i.e., November 15, 2010).

C. Southeast Desert One-Hour Ozone Nonattainment Area

In the Southeast Desert, CARB is the agency responsible for 

assuring that the area meets air quality monitoring 

requirements. The Antelope Valley Air Quality Management 

District (AVAQMD) operates monitors in the Los Angeles County 
23

portion of the Southeast Desert; the Mojave Desert Air Quality 

Management District (MDAQMD) operates monitors in the San 

Bernardino County portion of the Southeast Desert; and SCAQMD 

operate monitors in the Riverside County portion of the 

Southeast Desert. All three agencies submit annual monitoring 

network plans to EPA. These plans discuss the status of the air 

monitoring network, as required under 40 CFR section 58.10.

SCAQMD’s annual network plans and data certifications, as 

well as EPA’s TSA of SCAQMD’s ambient air monitoring program,

are discussed above in connection with the South Coast Air 

Basin. With respect to the annual network plans submitted by 

AVAQMD and MDAQMD, we have reviewed these plans and found that 

they meet the applicable requirements for such plans.

23 The TSA 

we conducted in 2007 of the CARB PQAO included a review of the 

network requirements in AVAQMD and MDAQMD. In the TSA, we 

concluded that the combined ambient air monitoring networks

operated by CARB and the air districts currently meet or exceed 

the requirements for the minimum number of SLAMS monitoring 

sites for ozone in the Southeast Desert. Also, AVAQMD and MDAQMD

 

23 See, e.g., letter dated April 30, 2008 from Sean P. Hogan, Manager, Air 

Quality Analysis Office, EPA Region IX, to Eldon Heaston, Executive Director, 

MDAQMD.
24

annually certify that the data submitted to AQS are qualityassured.24

There were nine ozone monitoring sites located throughout 

the Southeast Desert in calendar years 2005 through 2007: one 

in Los Angeles County, three in Riverside County, and five in 

San Bernardino County.

25 All of the sites monitor ozone 

concentrations on a continuous basis using ultraviolet 

absorption monitors.26 AVAQMD operates the one monitor in Los 

Angeles County. SCAQMD operates two of the three monitors in 

Riverside County; the third monitor is operated by the National 

Park Service at Joshua Tree National Park. MDAQMD operates four 

of the five sites in San Bernardino County; the fifth monitor is 

operated by the National Park Service at Joshua Tree National 

Park. 

Table 3 summarizes the ozone monitoring data from the 

various monitoring sites in the Southeast Desert, showing the 

expected exceedances per year and as an average over the 2005-

2007 period. The data summarized in Table 3 are considered 

 

24 See, e.g., letter dated June 27, 2007 from Chris Collins, A/Q Supervisor, 

MDAQMD, to Wayne Nastri, Regional Administrator, EPA Region IX, certifying 

calendar year 2006 ambient air quality data in both MDAQMD and AVAQMD.

25 See figures 5 and 11 from CARB’s State and Local Air Monitoring Network

Plan (June 2009) for illustrations of the locations of the ozone monitors 

within the Southeast Desert.

26 AVAQMD and MDAQMD operate federal equivalent method (FEM) monitors for 

ozone, specifically, Teledyne/API 400 series ultraviolet absorption monitors.
25

complete for the purposes of determining if the standard is 

met.

27

Table 3 – One-Hour Ozone Data for the Southeast Desert One-Hour 

Ozone Nonattainment Area

General Location

Site (AQS 

ID)

Expected 

Exceedances by 

Year

Expected 

Exceedances 

3-yr average

2005 2006 2007 2005-2007

Antelope Valley Lancaster

(06-037-

9033)

1.0 2.0 0.0 1.0

Coachella Valley Indio

(06-065-

2002)

0.0 0.0 0.0 0.0

Joshua Tree 

National Park

Cottonwood 

Visitor 

Center

(06-065-

0008)

NA 0.0 0.0 0.0

Coachella Valley Palm Springs 

(06-065-

5001)

4.0 2.0 1.0 2.3

Northern portion 

of SE Desert 

AQMA 

Barstow

(06-071-

0001)

0.0 0.0 0.0 0.0

SW portion of SE 

Desert AQMA

Hesperia

(06-071-

4001)

3.0 2.0 2.0 2.3

SW portion of SE 

Desert AQMA

Phelan

(06-071-

0012)

2.0 2.0 0.0 1.3

SW portion of SE 

Desert AQMA

Victorville

(06-071-

0306)

2.0 1.0 0.0 1.0

Joshua Tree 

National Park

Yucca Valley

(06-071-

9002)

2.0 1.0 1.0 1.3

 

27 The criteria for data completeness are met at all of the ozone monitors in 

the Southeast Desert over the 2005-2007 period except for the ozone monitor 

at the Joshua Tree National Park (06-065-0008). Despite the lack of complete 

data from that one monitor, sufficient data from the network as a whole exist 

to support the proposed determination of failure to attain the one-hour ozone 

NAAQS by the applicable attainment date within the Southeast Desert.
26

NA = No data is available. 

Source: Quicklook Report, May 11, 2011 (in the docket to this 

proposed action).

Generally, the highest ozone concentrations in the 

Southeast Desert occur in the far southwestern portion of the 

area, near mountain passes through which pollutants are 

transported to the Southeast Desert from the South Coast Air 

Basin. As shown in Table 3, the highest three-year average of 

expected exceedances at any site in the Southeast Desert for 

2005-2007 is 2.3 at Palm Springs in Riverside County and 

Hesperia in San Bernardino County. The calculated exceedance 

rate of 2.3 represents a violation of the one-hour ozone 

standard (a three-year average of expected exceedances less than 

or equal to 1).28

Taking into account the extent and reliability of the 

applicable ozone monitoring network, and the data collected 

therefrom and summarized in Table 3, we propose to determine 

that the Southeast Desert failed to attain the one-hour ozone 

standard (as defined in 40 CFR part 50, appendix H) by the 

applicable attainment date (i.e., November 15, 2007).

IV. What Is The Effect Of The Proposed Determinations?

 

28 A preliminary review of more recent data (2008-2010) for the Southeast 

Desert suggests that only one monitoring site (the site in Phelan, San 

Bernardino County) remains in violation of the one-hour ozone standard with a 

calculated expected annual exceedance rate of 1.7. However, due to the four 

exceedances recorded in 2010, the soonest that the Phelan site could be 

determined to be attaining the one-hour ozone standard will be in 2014 

(assuming such a determination is supported by 2011-2013 data).
27

A final determination of a Severe or Extreme area’s failure 

to attain by its one-hour ozone NAAQS attainment date would 

trigger the obligation to implement one-hour contingency 

measures for failure to attain under section 172(c)(9) and fee

programs under sections 182(d)(3), 182(f), and 185. Section 

172(c)(9) requires one-hour ozone SIPs, other than for 

―Marginal‖ areas, to provide for implementation of specific 

measures (referred to herein as ―contingency measures‖) to be 

undertaken if the area fails to attain the NAAQS by the 

attainment date. The effect of the proposed determinations would 

be to give effect to any one-hour ozone contingency measures 

that are not already in effect within the three subject 

California nonattainment areas. 

Section 182(d)(3) requires SIPs to include the provisions 

required under section 185, and section 185 requires one-hour 

ozone SIPs in areas classified as ―Severe‖ or ―Extreme‖ to 

provide that, if the area has failed to attain the standard by 

the applicable attainment date, each major stationary source of 

ozone precursors located in the area must begin paying a fee 

[computed in accordance with section 185(b)] to the State. 

Section 182(f) extends the section 185 requirements, among 

others, that apply to major stationary sources of VOCs to major 

stationary sources of NOx unless EPA has waived such requirements 

for NOx sources in the particular nonattainment area. 
28

 The three subject ozone nonattainment areas, the South 

Coast, the San Joaquin Valley, and the Southeast Desert, lie 

within the jurisdictions of four California air districts: the 

SCAQMD, the SJVUAPCD, the AVAQMD, and the MDAQMD. Each of the 

four air districts has adopted rules intended to comply with 

sections 182(d)(3) and 185 of the Act and CARB has submitted 

them to EPA for approval into the SIP. EPA has taken action on 

one of the rules, SJVUAPCD Rule 3170. See 75 FR 1716 (January 

13, 2010). Since then, SJVUAPCD Rule 3170 has been revised, and

EPA has recently proposed approval of the amended rule. See 76 

FR 45212 (July 28, 2011). EPA has not yet taken action on the 

rules developed by the other three districts (SCAQMD Rule 317, 

AVAQMD Rule 315, and MDAQMD Rule 315, all of which were

submitted on April 22, 2011). Another effect of the proposed 

determinations of failure to attain the 1-hour ozone standard by 

the applicable attainment dates would be to give effect to the 

section 185 requirements to the extent they are not already in 

effect within the three subject California nonattainment areas. 

V. Proposed Actions

Under EPA’s authority under CAA section 301(a) to ensure 

implementation of one-hour ozone anti-backsliding requirements,

EPA is proposing to determine that the South Coast, the San 

Joaquin Valley, and the Southeast Desert failed to attain the 

one-hour ozone standard by the applicable attainment dates. For 
29

South Coast and San Joaquin Valley, quality-assured and 

certified data collected during 2008-2010 show that these two 

―Extreme‖ one-hour ozone nonattainment areas failed to attain 

the standard by November 15, 2010. For Southeast Desert, a 

―Severe-17‖ one-hour ozone nonattainment area, quality-assured 

and certified data for 2005-2007 show that the area failed to 

attain the standard by November 15, 2007. 

These proposed determinations, if finalized, would bear on 

the areas’ obligations with respect to certain one-hour standard 

anti-backsliding requirements whose implementation is triggered 

by a failure to attain by the applicable attainment date: 

section 172(c)(9) contingency measures for failure to attain and 

sections 182(d)(3) and 185 major stationary source fee programs. 

Through this proposed rule, EPA is soliciting comments on the 

above determinations.

VI. Statutory and Executive Order Reviews

These actions propose to make determinations that certain 

areas did not attain the applicable standard based on air 

quality, and do not impose any requirements beyond those 

required by statute. For that reason, these proposed actions:

Are not a ―significant regulatory action‖ subject to review 

by the Office of Management and Budget under Executive 

Order 12866 (58 FR 51735, October 4, 1993);
30

Do not impose an information collection burden under the 

provisions of the Paperwork Reduction Act (44 U.S.C. 3501 

et seq.); 

Are certified as not having a significant economic impact 

on a substantial number of small entities under the 

Regulatory Flexibility Act (5 U.S.C. 601 et seq.);

Do not contain any unfunded mandate or significantly or 

uniquely affect small governments, as described in the 

Unfunded Mandates Reform Act of 1995 (Pub. L. 104–4);

Do not have Federalism implications as specified in 

Executive Order 13132 (64 FR 43255, August 10, 1999);

Are not economically significant regulatory actions based 

on health or safety risks subject to Executive Order 13045 

(62 FR 19885, April 23, 1997);

Are not significant regulatory actions subject to Executive 

Order 13211 (66 FR 28355, May 22, 2001);

Are not subject to the requirements of Section 12(d) of the 

National Technology Transfer and Advancement Act of 1995 

(15 U.S.C. 272 note) because application of those 

requirements would be inconsistent with the Clean Air Act; 

and

Do not provide EPA with the discretionary authority to 

address disproportionate human health or environmental 
31

effects with practical, appropriate, and legally 

permissible methods under Executive Order 12898 (59 FR 

7629, February 16, 1994). 

In addition, this proposed rule does not have tribal 

implications as specified by Executive Order 13175 (65 FR 67249, 

November 9, 2000), because the SIP is not approved to apply in 

Indian country located in the state, and EPA notes that it will 

not impose substantial direct costs on tribal governments or 

preempt tribal law.

List of Subjects in 40 CFR Part 52

Environmental protection, Air pollution control, 

Intergovernmental relations, Oxides of nitrogen, Ozone, 

Reporting and recordkeeping requirements, Volatile organic 

compounds.

___9/1/11_________ _______/s/______________

Dated: Jared Blumenfeld,

Regional Administrator,

Region IX.